Refrigerating apparatus.



W. COOPER.

REFRIGBBATING APPARATUS.

APPLICATION FILED JUNI; 7,1912,

1 ,085,1 1 1, Patented Jan. 27, 1914.

www il lull!! E 'resident of"`Wilkinsbur WILLIAM COOPER, 0F WILKINSBURG,PENNSYLVANIA.

REFBIGERATING ALPPABATUS.

Specification of Letters Patent.

Application filed J' une 7, 1912. Serial No. 702,297.

Patented Jam-27, 1914.

To all whom t may concern Be it known that I, WILLIAM COOPER, a inthecounty'of tflllegheny and State of Pennsylvania, have lnvented a newand useful Improvement in Refrigerating Apparatus, of which thefollowing is a specification.

This invention relates to refrigerating systems, and more especially tosystems of the absorption type.

The object of the invention is to produce a simple andinexpensivesystem, wherein a given amount of refrigeration can be produced at arelatively low cost, or in other words, one having a high efciency.

In my improved apparatus, the gas returning from the evaporating device'is conducted to suitable means which compresses it while in contact withthe weak solution coming from the generator and is thereby absorbedtherein, the resulting strong solution being thereby raised toapproximately the temperature and pressure of the generator. Thisarrangement enables the production and use ofa solution of comparativelyhigh strength, but the invention is not limited by the strength of thesolution. Preferably, an aqua solution of ammonia is usedv in theapparatus, and in the detailed description hereinafter the apparatus isdescribed as Vusing an aqua solution of ammonia, but it will beunderstood that the invention. is not limited to this particular gas.

The accompanying drawing represents diagrammatically an arrangement ofapparatus embodying my invention.

In the drawing, 1 indicates a suitable evaporating device in whichliquid or anhydrous ammonia is evaporated to produce the refrigeratingeffect. This may be of any preferred type, and as shown consists of atank in which the anhydrous ammonia evaporates around4 the coils 2 of abrine Vcirculating system, and through which brine or any othernon-congealable 4liquid is passed to enable the refrigerant to beconducted to any desired location.

The ammonia is distilled in a generator 3 by the application of heatfrom any suitable source as, for example, steam pipes 4, the steam beingsupplied from any suitable source. The generator or still 3 is'filledwith aqua solution of ammonia which may be of comparatively highstrength, say from 70 to 80 per cent. of ammonia by weight in water.Thejammonia gas distilled in the generator 3 passes oil' through aconnection 6 to a condenser-7 of any preferred type, in the presentinstance being shown as a tank having water connections 8 for passingcooling Watertherethrough and around the coils 9 through which theammonia passes.

In the condenser 7 the anhydrous ammonia is cooled and liquefied and itis then passed through a conduit or connection 15 to the evaporatingdevice 1 referred'to. In the connection 15 may placed a suitable storagetank 16 for the liquefied anhydrous ammonia, if desired. c. The4pressure in the generator 3 in practice is about one hundred and fiftypounds to the square inch, depending upon the temperature of the-cooling water used in the condenser. The evaporating device 1 isoperated under comparatively low pressure, say about fifteen pounds persquare inch. To reduce the pressure of the ammonia as it flows from thecondenser 7 to'the evaporating device 1, a suitable expansion valve 17,of any preferred type, is placed in the connection 15 between `thecondenser 7 and evaporating device 1.

The present refrigerating system is of the continuous type and is soarranged that as the ammonia is evaporated in the evaporating device 1,it is combined with weak liquor fiowing from the generator 3. The weakliquor flows yfrom the generator 3 through s1 conduit or connection 20and then through a suitable cooling device 21, shown as a pipesurrounding the connection 20 and provided with connections 22 forpassing cooling water therethrough. The weak liquor is returned to thegenerator 3 by a pump 23 of any suitable form, but preferably of therotary or turbine type, able means, such as a steam engine. A reducingvalve 24 is placed in the connection 20 between the generator and thepump 23. The ammonia gas passing olf from vthe evaporating device 1 isled through a connection 25 and is mingled with the weak liquor passingthrough the pump 23, the combinedliquor and gas, now in the form ofstrong liquor, being returnedto the generator 3 by a connection 26 fromthe punip 23. l f

The operation of the apparatus is as follows: The pressure inthegenerator er still 3, as stated, is high, sayabout one hundred and ftypounds to the square inch, while and driven by any suitv that in theevaporating device l is low, and about fifteen pounds per square inch.Assuming that the Weak solution coming from the generator 3 through theconnection 20 is 70 per cent. ammonia byweight and that its temperatureis about 140 F., this liquor Will be oooled in the cooler 21 to atemperature of say 80 F., depending upon the temperature of the coolingWater.A As the `Weak liquor passes through reducing valve 24, itspressure is reduced from one hundred and fifty pounds to fteen poundsper lsquare inch, that is, to the pressure of the evaporating device. Ata temperature of 80 F.

`and a pressure of fteen pounds per square inch some of the amlnonia gascontained in the solution escapes, sinoega 70 per cent. solution of aquaammonia can only be had at fifteen pounds pressure by reduction of thetemperature to at least 40 F. The escape of this excess ammonia gas fromthe solution cools the solution to 40 F., about tifteen per cent. of theammoniav in the solution evaporating to obtain this reduction intemperature. The ammonia gas escaping from the evaporator 1 is at apressure of about ifteen pounds per square inch. As a result of theconnections described, there is led to the pump a mixture of solution ofaqua ammonia at 40 F. and unabsorbed ammonia gas, this mixture beingsupplied jointly by the connections 20 and 25. The pump 23 illustratedis of the turbine type, but may be of any form which Will cause anintimate mixture and mingling of the gas and liquor to promote rapid andquick absorption of the gas in the liquor. It gradually raises thepressure of the solution and gas passing therethrough. If it so happens,in the case given, that no ammonia gas is'being supplied by theconnection 25 from the evaporating device, the free gas coming with thesolution through the connection 20 from the generator will all return tothe solution when the pressure reaches fifty pounds per square inch, thetemperature of the solution then being 80 F. The pump, however,continues to raise the pressure of the`solution and with a solution ofthe strength and pressure stated, considerable additional ammonia gascan be added to bring the'pressure and temperature up to the pressureand temperature of the generator. In practice the solution absorbs theammonia gas which is supplied by the'connection 25 from the evaporatingdevice 1. The operation and effect of the pump 23 will, therefore, givea solution of about 78.5 per cent. ammonia by weight at a` temperatureof say 120 F., the minimum temperature ofv the generator. The ammoniagas addedto the solution is just the amount Vnecessar ture of the4solution to that of the generator at the pressure existing Ain thegenerator.

to increase the tempera-v With a system embodying my invention, asolution of aqua ammonia of such high strength in ammonia by Weight `maybe used that the total quantity of solution to produce a givenrefrigerating eect is very materially reduced. Also, the stron er thesolution, the less heat required to istil a given quantity of gas. Thepump 23 causes a very thorough stirring up of the solution passingthrough and secures' intimate contact betwen the unabsorbcd gas and theent-ire body of solution so that the gas readily and quickly enters intosolution as the pressure is increased. It acts both as an absorber tocause the ammonia gas to reenter the solution and as a mechanical pumpto raise the pressure of the solution from thatof the evaporator to thatof the generator. It dispenses with an absorber of the type usuallyemployed and with the usual interchanger and materially simplifies theapparatus. The'expansion valve 17 and the reducing valve 24 cont-rol thepressure in the evaporating system and will be so regulated as to securethe most eicient operation. The operation is carried on continuously andthe liquor returned to the generator 3 may be so regulated as to enterthe same at approximately the existing temperature and pressure therein.y

1. In an absorption refrigerating system,

the combination of a generator, an evaporator, and a single means havingconnections to the generator and to the evaporator and arranged to bothcause the evaporated refrigerant to be absorbed in the weak solutioncoming from the generator and to also return theresultant solution tothe generator.

2. In an absorption reirigerating system, the combination of agenerator, an evaporator, and a single means having connections on oneside to the enerator and evaporator and on its other sidebeing connectedto the generator and arranged to receive the evaporated refrigerant fromthe evaporator and cause it to be absorbed in the weak solution comingfrom the generator and compress the same and to also conduct theresultant solution to the generator.

3. In an absorption refrigerating system, the combination of agenerator, an evaporator, a rotary pump having its suction sideconnected to the generator and evaporator and arranged to receive theWeak solution and evaporated refrigerant and cause the refrigerant to beabsorbed in the solution, and having its the generator for conductingthe resultant solution thereto.

4. In an absorption refrigerating System, the combination of agenerator, an evaporating device, a puin connected to said generator tocirculate liquid `therethrough, and a `vice, a pump arranged to deliverstrong connection between said evaporating device I and said pump fordelivering evaporated refrigerant to said pump. i

In an absorption refrigerating system, the combination oil a generator,an evaporati ing device, a pump connected on one side with the generatorand evaporating device, f said pump being arranged to compress ievaporated refrigerant coming from said evaporating device and cause itto be ab sorbed by the weak solution coming from j said generator, and areturn connection from the other side of said pump to the generator forreturning the strong solution thereto.

6. In an absorption refrigerating system, the combination of agenerator, an evaporating device, a pump connected on its suction sideto said evaporating device and generator, a cooler for the weak solutioncoming from said generator, and a connection from the discharge side ofthe pump to the generator for delivering the resultant strong solutionthereto.

7. In an absorption refrigerating system, the combination of agenerator, a condenser, an evaporating device, an expansion valvebetween said condenser and evaporating desolution to said generator, anda connection between said evaporating device and said pump.

8. In an absorption retrigerating system, the combination of agenerator, a condenser, an evaporating device, an expansion valvebetween said condenser and evaporating device, a pump having connectionto said lenerator and arranged to circulate liquid therethrough, areducing valve in said connection, and a connection between saidevaporating device and said pump.

9. In an absorption refrigerating system, the combination of agenerator, a condenser, an evaporating device, an expansion valvebetween said condenser and evaporating device, a pump having connectionfor circulating liquid through said generator, a reducing valve and a.cooler for the weak solution in'said connection, and a connectionbetween said evaporating device and said pump.

In testimony whereof, I have hereunto set my hand.

WILLIAM COOPER.

Witnesses i ELBERT L. HYDE, WILLIAM B. WHAR'roN.

